Seat in particular a vehicle seat preferably an aeroplane seat

ABSTRACT

The invention relates to a seat with a first seat piece ( 10 ) and a further seat piece ( 12 ), which may be adjusted for inclination by means of a controllable operating device ( 14 ). Said operating device ( 14 ) engages with the further seat piece ( 12 ) by means of at least two adjusters ( 30 ), which are moved by a common drive mechanism ( 34 ) with a mechanical coupling ( 36 ) between the adjusters ( 30 ), for an effectively uniform motion thereof. A uniform inclination adjustment of the further seat piece, such as backrest and/or legrest is achieved, whereby the drive comprises an actuator device with a longitudinally displaceable operating piece ( 40 ), engaged with a rocker ( 44 ), connected to an adjuster piece ( 30 ) and operating the mechanical coupling ( 36 ), with a further rocker ( 46 ), for the other adjuster ( 30 ).

[0001] The invention relates to a seat, in particular a vehicle seat, preferably an aeroplane seat, with a first seat part, and another seat part which can be adjusted in tilt by way of a triggerable actuating means, the actuating means engaging the other seat part with at least two adjustment parts which can be moved by a common drive, and its uniform movement of the adjustment parts in this respect causing mechanical coupling between them.

[0002] A pertinent aircraft passenger seat is described in DE 199 44 620 which was published subsequently. This aircraft passenger seat consists of individual seat components including a leg rest and a backrest. These seat components can be moved by actuating means which can be triggered by a hand-operated actuating means for adjusting the seat to the requirements of the seat occupant. There are hand levers for the seat parts which are modeled to the contours of these seat parts as an element of the actuating means and which combined in one operating part for adjusting the aircraft passenger seat result in meaningful adjustment for the seat parts.

[0003] In all known tilt adjustment means for seat parts such as a backrest or leg rest, depending on the actuating and tilt adjustment means used at the time, obstacles can arise since generally the actuating means engages only one point of the backrest and/or leg rest; this leads to twisting or torsion of the other seat part which is to be adjusted in its tilt, even if minor twisting or torsion, so that a uniform swivelling motion cannot be achieved with a good feeling of the body for the seat occupant. Also, depending on the adjustment structure being used, in case of a crash, unilateral loading of the actuating means, especially in the form of a servo-drive, occurs, the latter often not being able to accommodate the forces which suddenly occur.

[0004] DE-A-33 35 486 A1 discloses a device for adjusting the height and the tilt of the backrest of the seat, especially of a motor vehicle seat. For selective adjustment of the tilt of a backrest or the height of the entire seat by means of a single drive spindle, it consists of two spindle parts which each bear, a mating non-rotatable bevel wheel which interacts with a bevel wheel on the spindles of individual adjustment mechanisms, and they are connected non-rotatably only in a certain relative axial position by way of gear rings. In this position only one mating bevel wheel meshes with the assigned bevel wheel, while in the other relative axial position of the two drive spindle parts the two mating bevel wheels mesh with the assigned bevel wheels, but the non-rotatable connection between the two drive spindle parts is canceled. The known gear approach has a plurality of bevel wheels which fit into one another at a right angle so that the known approach takes up a relatively large amount of construction space on the respective vehicle seat, and besides, is accordingly heavy. Furthermore, the approach based on a plurality of individual components is structurally complex and moreover expensive to produce.

[0005] DE-A-34 12 047 A1 discloses a generic device for adjusting the tilt of the backrest of a seat, especially for motor vehicles with a backrest frame with two laterally arranged rotary fittings, which is driven by way of intermediate pinion gears by a drive shaft which is supported in the seat frame and is driven by way of a synchronous belt drive from a handwheel supported on the front end of the seat frame. As a result a continuous shaft is not necessary in the backrest, and the handwheel for driving the seat back adjustment is located at a favorable site which is easy to reach. Since synchronous belt drives with their drive wheels and shafts are fundamentally subject to a certain slip behavior, there is no smooth and uniform triggering of the adjustment motion on the two lengthwise sides of the backrest, and obstacles in operation must be expected. Furthermore, the known and aforementioned approaches have the disadvantage that they are hardly suitable for reliably accommodating the peak loads which occur in the seat base structure in case of a crash, if it is being used in the vehicle domain, especially in the aircraft domain.

[0006] Based on this prior art, the object of the invention is to further improve the known seats such that unhindered and uniform tilt adjustment operation of the entire further seat part, such as a backrest or a leg rest, is achieved and that in case of a crash, when peak loads occur, they can be reliably accommodated by the seat structure of the vehicle seat, also in the form of an aircraft passenger seat. Furthermore, economical tilt adjustment with a simple structure is to be implemented. The object is this respect is achieved by a seat with the features of claim 1.

[0007] In that, as specified in the characterizing part of claim 1, the drive consists of an actuating means with an actuating part which can be moved lengthwise and which engages an angle drive which is coupled to the adjustment part and which actuates the mechanical coupling, and because for the other adjustment part there is another angle drive, uniform tilt adjustment for another seat part, such as a backrest and/or leg rest, is achieved.

[0008] As a result of the mechanical coupling, the indicated seat parts can be uniformly swivelled over their entire width and consequently can be adjusted in tilt around a respective common swivelling axis, so that unilateral application of force with its adverse effects is avoided. Since as a result of the uniform application of force by way of the two adjustment parts and the mechanical coupling between these two parts, torsion forces within the other seat part and its resulting twisting are avoided, a load on the articulation points which form the swivelling axis is also avoided, by way of which points the other seat part, such as the backrest or leg rest, is coupled to the actual seat part of the seat. Furthermore, the mechanical coupling allows relief of the actuating means, for example in the form of a servo-drive so that peak loads in case of a crash can be directly accommodated by the mechanical coupling and can be diverted into the seat frame. The approach as claimed in the invention is light in structure; this makes its use in aircraft especially efficient and it is moreover economical to produce and as a result of the mechanical approach low maintenance costs and few failures can be expected.

[0009] The actuator means which are used are economically available commercially and are reliable in operation. Furthermore, in this way it is possible to convert a small motion of the actuator or servo-drive into a corresponding path of motion for the adjustment part by way of the indicated angle drive, so that a uniform and visible tilt adjustment for the other seat part is achieved. Furthermore, the angle drive allows deflection of the force applied by way of the actuating part, preferably in the form of an actuating rod of the actuator means in the direction of the adjustment part at almost a right angle, so that reliable, dedicated tilt adjustment is possible in spite of the tight installation conditions within the seat frame.

[0010] In one preferred embodiment of the seat as claimed in the invention, the mechanical forced coupling consists of a rigid component which is hinged to the angle drives. A load situation which has been initiated in case of a crash by way of the indicated adjustment parts can consequently be reliably accommodated by way of the rigid component with relief of the actuator. By preference, the rigid component extends as mechanical coupling transversely to the lengthwise direction of the seat in order in this way to keep the base contour of the seat frame clamped; this distinctly increases the passive safety for the seat.

[0011] In another preferred embodiment of the seat as claimed in the invention, the actuator housing is rigidly connected to the seat frame for the seat part or is coupled to the other angle drive. In the latter case actuation of the actuator leads equally to an adjustment motion of the actuator housing and the actuating rod so that with only one actuating process, by way of these two parts, an adjustment path twice as large for the angle drive can be traversed. Preferably, it is provided for reliable operation that the actuator housing is rigidly held on the seat frame and driving for the angle drives with the adjustment parts takes place only by way of the actuating rod and the mechanical coupling.

[0012] The indicated tilt adjustment device can fundamentally be used for all parts of a seat which must be adjusted preferably in their tilt. But it has been found to be especially advantageous to use the tilt adjustment device for tilt adjustment of the backrest of an aircraft passenger seat.

[0013] Other advantageous embodiments of the seat as claimed in the invention are the subject matter of the other dependent claims.

[0014] The indicated seat in its configuration as claimed in the invention can also be used as a medical treatment chair in surgery and at dentists, and also as a chair for application of cosmetics, and the like.

[0015] But the seat as claimed in the invention is detailed below using one embodiment of an aircraft passenger seat as shown in the drawings. The seat as claimed in the invention however can be effectively used not only in an aircraft, but also on ferries, cruise ships, busses and the like.

[0016] The figures are schematic, not drawn to scale, and show partial sections.

[0017]FIG. 1 shows a side view of the seat frame of an aircraft passenger seat without the leg rest and with the backrest mechanism only partially shown;

[0018]FIG. 2 shows, in a perspective view, part of the seat frame for the seat as shown in FIG. 1 with a tilt adjustment for a backrest which is not detailed in particular;

[0019]FIG. 3 shows an overhead view of the partial sections of a seat frame as shown in FIG. 2, after it has been swivelled clockwise around its lengthwise axis “X” which is shown by the broken line as indicated by 180°, in the direction of looking at FIG. 2;

[0020]FIG. 4 shows a side view of the partial sections of the seat frame in the arrow direction designated “Y” as shown in FIG. 3.

[0021] The embodiment of a vehicle seat as claimed in the invention as shown in FIG. 1 is an aircraft passenger seat, as is conventionally used in airliners for passengers, for better representation the cushion parts and the leg rest for the seat occupant having been omitted. The aircraft passenger seat has a first seat part 10 and another seat part 12 with adjustable tilt in the form of a backrest. The pertinent backrest is positioned to be able to swivel by way of an actuating means designated as a whole as 14 in its tilt relative to the essentially horizontally running first seat part 10. The first seat part 10 can in turn be erected on the vehicle floor by way of stationary legs 16 using seat rails 18. As illustrated, especially by FIGS. 2 and 3, the pertinent seat structure as shown in FIG. 1 is essentially doubled in a successive arrangement and in this way constitutes a seat frame 20. The pertinent structure is conventional in aircraft passenger seats so that it will not be detailed here.

[0022] For tilt adjustment, the backrest 12 with its fittings is positioned to be able to swivel around a swivelling axis 22 which is supported in the side walls 24 of the seat frame 20. To implement the pertinent support, the backrest 12 with its two fitting parts on the lengthwise sides has a forked piece 26 on its bottom, on the free end of the other fork end piece there being a coupling point 28 for triggering the tilt adjustment of the backrest 12 around the actual swivelling axle 22. This structure is detailed below, for the sake of clarity FIGS. 2 and 4 showing only the fork end piece to the extent this relates to the indicated coupling point 28. In order to furthermore implement a lightweight construction for an aircraft passenger seat, as shown in the figures, both in the seat rails 18 and also in the side walls 24 of the seat the wall pieces are accordingly recessed, without endangering the structural safety of the seat.

[0023] The actuating means 14 has two rod-like adjustment parts 30 which with their one free end engage the other seat part 12 in the form of a backrest by way of a fork end piece 32 which is pivotally connected to the aforementioned coupling point 28 of the respective fitting part for the backrest 12. For greater clarity, FIGS. 2 and 4 each show only one fitting part of the indicated backrest 12 as a further seat part, the arrangement shown in this way also applying comparably to the other fitting part 12 of the backrest of the aircraft passenger seat, which part is not detailed.

[0024] The two rod-like adjustment parts 30 can be moved by way of a common drive 34, for a respective uniform motion of the two adjustment parts 30 there being mechanical forced coupling 36 which acts between them. The drive 34 consists of a conventional actuator means which is not detailed, with an actuating rod 40 which can be moved lengthwise by way of the drive motor 38 which is guided in the actuator housing 42. As FIG. 3 shows in particular, the actuating rod 40 with its free end engages a first angle drive 44 and one of its free ends in an articulated manner. This first angle drive 44 in turn on its other free end engages the rod-shaped adjustment part 30 in an articulated manner. Furthermore, the angle drive 44 is connected to the already addressed mechanical coupling 36. Furthermore, for the other adjustment part 30 there is another, second angle drive 46, the mechanical coupling 36 consisting of a rigid component in the form of a coupling rod 48 which is hinged by each of its two free ends to the two angle drives 44, 46. For the sake of clarity, in FIG. 2 the angle drives 44, 46 with the adjustment parts 30 and with the coupling rod 48 are shown as not connected to one another, in the manner of an exploded drawing. This also applies to the arrangement as shown in FIG. 3, to the extent the two angle drives 44, 46 are shown not joined to the free ends of the two end parts 30 which are located opposite, adjacent to the coupling point 28.

[0025] In this embodiment, the actuator housing 42 is rigidly connected to the seat frame 20 for the seat part 10 so that after actuating the drive motor 38, preferably in the form of an electric motor, with the actuator housing 42 stationary, the actuating rod 40 can be telescoped depending on the desired direction. In one embodiment which is not detailed, it would however also be possible to hinge the free end of the actuator housing 42 to the second angle drive 46 so that when the actuator is actuated the two angle drives 44, 46 are uniformly swivelled towards one another or away from one another. The pertinent, common swivelling motion is however itself achieved for an actuator housing fixed on one side in any case by way of the mechanical forced coupling 36 in the form of the coupling rod 48. In this respect synchronous running of the two adjustment parts 30 and consequently smoothly running tilt adjustment for the backrest 12 are achieved.

[0026] The respective angle drive 44, 46 has two angle arms 50, 52, of which one angle arm 50 is coupled to the pertinent adjustment part 30, and the other angle arm 52 has an engagement point 54 in articulated form for the coupling rod 48. Furthermore, between the two arms 50, 52 of each angle drive 44, 46 there is a swivelling point 56 which enables coupling of the angle drives 44, 46 to the crosspiece 58 of the seat frame 20, viewed in the direction of looking at FIG. 3 the two angle drives 44, 46 being able to swivel clockwise and counterclockwise around the pertinent swivelling points 56. Furthermore, the engagement point 54 for the coupling rod 48 in the area of the first angle drive 44 is located between the coupling point of the actuating rod 40 and the swivelling point 56 for this angle drive 44. The actuating means 40 therefore extends, as shown in FIG. 3, protected between the first crosspiece 58 and another crosspiece 60 which in turn runs parallel to the first crosspiece 58. Furthermore the actuator housing 42 is connected to the first crosspiece 58 by way of a reinforcing angle 62.

[0027] For the sake of better understanding, the described invention is detailed below based on its operation. When the seat occupant actuates a corresponding actuating switch to move the backrest 12 back in the direction of a rest position, he starts the electric drive motor 38 and the actuating rod 40 travels linearly into the actuator housing 42 which is otherwise held in the seat frame 20. In doing so the first angle drive 44 swivels counterclockwise around the swivelling point 56 in the first crosspiece 58 and the arm 50 pulls back the assigned rod-shaped adjustment part 30, i.e., the adjustment part 30 is moved from right to left viewed in the direction of looking at FIG. 3, so that the coupling point 28 for the fitting part of the backrest 12 is likewise pulled in this direction. The pertinent displacement process however affects not only the adjustment part 30 which is the upper one viewed in the direction of looking at FIG. 3, but also the underlying bottom adjustment part 30. In the swivelling motion of the first angle drive 44 counterclockwise, it is pressed down by the coupling rod 48 viewed in the direction of looking at FIG. 3 and by way of the engagement point 54 on the second angle drive 46 the latter is swivelled clockwise around the assigned swivelling point 56. But the arm 50 of the second angle drive likewise backs out the lower adjustment part 30 by the pertinent swivelling motion, i.e., the coupling point 28 is likewise moved from right to left. Since consequently via the coupling 36 in the form of the coupling rod 48 the two angle drives 44, 46 are forcibly guided in their motion, the pertinent swivelling motion takes place synchronously and the two adjustment parts 30 are uniformly and smoothly moved back at the same time. Since, as already shown, the backrest 12 is swivelled around the swivelling axis 22, when the two adjustment parts 30 are pulled into the seat frame the coupling point 28 is likewise pulled in the direction of the seat frame and by way of the respective fork end piece 32 (cf. FIG. 1) swivels the backrest 12 viewed in the direction of looking at FIG. 1 clockwise around the swivelling axis 22 into a possible rest position.

[0028] To reverse this process, after corresponding actuation of the control switch by way of the respective seat occupant the electric drive motor 38 is shifted into the drive direction such that the actuating rod 40 of the actuator is extended, the first angle drive 44 then being swivelled clockwise, and by way of the mechanical forced coupling in the form of the coupling rod 48 the second additional angle drive 46 is swiveled uniformly, but in the opposite direction. In the pertinent adjustment motion then the two rod-shaped adjustment parts 30 are pushed out of the seat frame and the fitting parts of the backrest 12, due to the respective fork end piece 32, for the raising motion swivel counterclockwise around the swivelling axis 22 until for example an almost upright backrest position as shown in FIG. 1 is reached.

[0029] If in case of a crash a sudden load is applied to the backrest, in which the seat occupant presses the backrest 12 to the rear, the two adjustment parts 30 are possibly likewise pressed suddenly in the direction of the interior of the seat frame 20, the angle drives 44, 46 which are then pushed in opposite directions against one another being mutually locked by way of the mechanical coupling 36 (coupling rod 48) and the mechanical parts which are designed to be rigid directly accommodating the sudden crash load without its being diverted into the elastic actuator-actuation system. Additionally the tilt adjustment means enables a continuous uniform motion on the two lengthwise sides of the backrest by way of the assignable fitting parts so that torsional warping of the backrest 12 is precluded and the swivelling axis 22 which is designed for tilting is relieved accordingly. The indicated tilt position need not be limited to an application in backrests, but can also be used for example for the leg rest, as optionally for tilt adjustment of the actual seat part 10 (not shown). In addition to the described electrical actuator means, optionally hydraulically operating actuating means or spindle drives can also be used. Since in the latter case, for a linear extension motion the actuating rod 40 must then be turned by way of its screw thread, a corresponding rotary guide must be provided in the area of the coupling point of the first angle drive 44 in order to be able to convert the rotary motion of the spindle drive directly into swivelling motion for the angle drive 44. 

1. Seat, in particular a vehicle seat, preferably an aeroplane seat, with a first seat part (10), and another seat part (12) which can be adjusted in tilt by way of a triggerable actuating means (14), the actuating means (14) engaging the other seat part (12) with at least two adjustment parts (30) which can be moved by a common drive (34), and for uniform movement of the respective adjustment parts (30) causing mechanical coupling (36) between them, characterized in that the drive (34) consists of an actuator means with an actuating part (40) which can be moved lengthwise and which engages an angle drive (44) which is coupled to the adjustment part (30) and which actuates the mechanical coupling (36), and that for the other adjustment part (30) there is provided another angle drive (46).
 2. The seat as claimed in claim 1, wherein the mechanical coupling (36) consists of a rigid component which is hinged to the angle drives (44, 46).
 3. The seat as claimed in claim 2, wherein the actuator housing (42) is rigidly connected to the seat frame (20) for one seat part (10) or is coupled to the other angle drive (46).
 4. The seat as claimed in claim 3, wherein the respective angle drive (44, 46) has two angle arms (50, 52), of which one angle arm (50) is coupled to the adjustment part (30), and the other angle arm (52) has an engagement point (54) for the coupling (36) and wherein between the two arms (50, 52) of each angle drive (44, 46) there is a swivelling point (56) with parts of the seat frame (20) around which the angle drives (44, 46) are pivotally held.
 5. The seat as claimed in claim 4, wherein as the mechanical coupling (36) there is a coupling rod (48) which engages the second arm (52) of the respective angle drive (44, 46) and wherein the end of the coupling rod (48) which engages one angle drive (44) accomplishes the engagement between the swivelling point (56) and the engagement point (54) of the actuating rod (40) on this angle drive (44).
 6. The seat as claimed in claim 4 or 5, wherein the swivelling points (56) of the angle drives (44, 46) are located on a common crosspiece (58) of the seat frame (20) which extends parallel to the axis of motion of the actuator, and which runs transversely to the two side walls (24) of the seat frame (20) along which the adjustment parts (30) for the backrest extend as another seat part (12).
 7. The seat as claimed in claim 6, wherein the individual parts (30) are made as adjustment rods which with their one free end engage the angle drives (44, 46) assigned to them respectively and with their other free end respectively engage one fitting part which extends at least partially along the lengthwise sides of the backrest (12).
 8. The seat as claimed in claim 6 or 7, wherein the actuating means (14) extends between one crosspiece (58) and the other crosspiece (60) of the seat frame (20) and wherein the actuating means (34) is provided with a drive motor (38). 